1. Technical Field
The present application relates to lighting power supply devices, and more particularly to an LED constant-voltage dimming power supply and dimming system for LED lamp having same.
2. Description of the Related Art
Light emitting diode (LED) is growing in popularity due to decreasing costs and long life compared to incandescent lighting and fluorescent lighting. LED lighting can also be dimmed without impairing the useful life of the LED light source.
In the prior art, one of many methods of dimmer is adopted to change current loaded on an LED lamp so as to change output power of the LED lamp. However, the dimmer method of changing current is limited to only supply for resistance current-limiting LED load. When it is used to supply for an LED lamp which have built-in DC-DC driver or an LED lamp which is a linear current regulative, these LED lamp will twinkle. On the other hand, since circuit itself has resistance, if a lot of loads adopt the dimmer method of changing current, it will result in different luminance among the different loads as different loads have different current flowing thererinto. Therefore, the LED driver having the dimmer method of changing current will have low universality and low consistency.
Therefore, it is necessary to provide an LED constant-voltage dimming power supply and dimming system for LED lamp having same to solve the above problem.